1 files changed, 120 insertions, 0 deletions
diff --git a/dom/worklet/WorkletFetchHandler.h b/dom/worklet/WorkletFetchHandler.h
new file mode 100644
index 0000000000..a380caf9eb
--- /dev/null
+++ b/dom/worklet/WorkletFetchHandler.h
@@ -0,0 +1,120 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef mozilla_dom_WorkletFetchHandler_h
+#define mozilla_dom_WorkletFetchHandler_h
+
+#include "mozilla/dom/PromiseNativeHandler.h"
+#include "mozilla/dom/RequestBinding.h"  // RequestCredentials
+#include "nsIStreamLoader.h"
+
+namespace mozilla::dom {
+class Worklet;
+struct WorkletOptions;
+class WorkletScriptHandler;
+
+namespace loader {
+class AddModuleThrowErrorRunnable;
+}  // namespace loader
+
+// WorkletFetchHandler is used to fetch the module scripts on the main thread,
+// and notifies the result of addModule back to |aWorklet|.
+class WorkletFetchHandler final : public nsISupports {
+ public:
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS(WorkletFetchHandler)
+
+  static already_AddRefed<Promise> AddModule(Worklet* aWorklet, JSContext* aCx,
+                                             const nsAString& aModuleURL,
+                                             const WorkletOptions& aOptions,
+                                             ErrorResult& aRv);
+
+  // Load a module script on main thread.
+  nsresult StartFetch(JSContext* aCx, nsIURI* aURI, nsIURI* aReferrer);
+
+  void ExecutionFailed();
+  void ExecutionFailed(JS::Handle<JS::Value> aError);
+
+  void ExecutionSucceeded();
+
+  void HandleFetchFailed(nsIURI* aURI);
+
+ private:
+  WorkletFetchHandler(Worklet* aWorklet, Promise* aPromise,
+                      RequestCredentials aCredentials);
+
+  ~WorkletFetchHandler();
+
+  void AddPromise(JSContext* aCx, Promise* aPromise);
+
+  void RejectPromises(nsresult aResult);
+  void RejectPromises(JS::Handle<JS::Value> aValue);
+
+  void ResolvePromises();
+
+  friend class StartFetchRunnable;
+  friend class loader::AddModuleThrowErrorRunnable;
+  RefPtr<Worklet> mWorklet;
+  nsTArray<RefPtr<Promise>> mPromises;
+
+  enum { ePending, eRejected, eResolved } mStatus;
+
+  RequestCredentials mCredentials;
+
+  bool mHasError = false;
+  JS::Heap<JS::Value> mErrorToRethrow;
+};
+
+// A Runnable to call WorkletFetchHandler::StartFetch on the main thread.
+class StartFetchRunnable final : public Runnable {
+ public:
+  StartFetchRunnable(
+      const nsMainThreadPtrHandle<WorkletFetchHandler>& aHandlerRef,
+      nsIURI* aURI, nsIURI* aReferrer);
+  ~StartFetchRunnable() = default;
+
+  NS_IMETHOD
+  Run() override;
+
+ private:
+  nsMainThreadPtrHandle<WorkletFetchHandler> mHandlerRef;
+  nsCOMPtr<nsIURI> mURI;
+  nsCOMPtr<nsIURI> mReferrer;
+};
+
+// WorkletScriptHandler is used to handle the result of fetching the module
+// script.
+class WorkletScriptHandler final : public PromiseNativeHandler,
+                                   public nsIStreamLoaderObserver {
+ public:
+  NS_DECL_THREADSAFE_ISUPPORTS
+
+  WorkletScriptHandler(Worklet* aWorklet, nsIURI* aURI);
+
+  void ResolvedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                        ErrorResult& aRv) override;
+
+  NS_IMETHOD
+  OnStreamComplete(nsIStreamLoader* aLoader, nsISupports* aContext,
+                   nsresult aStatus, uint32_t aStringLen,
+                   const uint8_t* aString) override;
+
+  void RejectedCallback(JSContext* aCx, JS::Handle<JS::Value> aValue,
+                        ErrorResult& aRv) override;
+
+  void HandleFailure(nsresult aResult);
+
+ private:
+  ~WorkletScriptHandler() = default;
+
+  void DispatchFetchCompleteToWorklet(nsresult aRv);
+
+  RefPtr<Worklet> mWorklet;
+  nsCOMPtr<nsIURI> mURI;
+};
+
+}  // namespace mozilla::dom
+#endif  // mozilla_dom_WorkletFetchHandler_h